You seem to have forgotten your history.
The panthers marched with guns (later called "copwatching") and even though I wasn't around for it I don't recall ever hearing of large scale violence as a result. Your suggestion that a black man couldn't carry an AR-15 and peacefully protest is unfounded not only in history but also in fact. In 1968 gun control legislation was passed en masse in response to the black panthers (read: black people) observing their 2A rights. Look into the Mulford Act in California in particular. The civil rights movement was nearly co-opted by agitators in the The Weather Underground. This is no different than Antifa co-opting these lawful protests to create domestic terror.
The "Trump let armed white nationalists storm the capitol" is false at it's face and the only people who believe it, and I mean this seriously, get their opinions from the likes of Don Lemon, Trevor Noah, and Anderson Cooper. They are the three horsemen spinning this narrative. Pay attention to who you listen to. You are being manipulated by gladhands masquerading as virtuous vanguards of truth.
For the last 7 days rioters have been on the door steps of the Whitehouse with zero intentions of a peaceful protest. These are not the same people. Nor do they want, care, or desire to see something actually done for police injustice. They want chaos. They are marxist agitators. If you think marxist is overstepping I'd invite you to go find any stream from the nights in DC and listen to their chants.
Sitting from my armchair command post BLM's best choice is to disband the protests, disavow any involvement in the rioting, and attempt to stage a later protest peacefully with more awareness about agitators and agent provocateurs.